Thanks, that is a good idea.  To see it in context:

        WHILE TRUE
           c = getChar()
           WHEN c == File.eof BREAK
           WHEN c == 0 CONTINUE
           handle(c)
        }

I would restrict this to using a statement that is a keyword.  Trying to
do something else, an assignment for example, goes into the direction of
code that is hard to read and easy to make mistakes:

           WHEN c == File.eof && fooOk blah = this & that

Adding a ";" in there won't help much.

At the moment, considering the remarks, I would rather stick with with a
normal IF.  It's three lines, but avoids that the programmer has to make
a choice.  And the choice is not always obvious.  Being a bit verbose is
not that much of a problem:

        WHILE TRUE
           c = getChar()
           IF c == File.eof
             BREAK
           }
           IF c == 0
             CONTINUE
           }
           handle(c)
        }

I agree that having WHILE at the start of the line makes a larger piece
of code easier to read.

Putting the label after the condition will make it difficult to find
when using a long condition:

         WHILE sadfasdf == asdfasdf.asdf.asdf()
             && asdfasdfdsf > asdf.asdf.asd.fasdf() : label

Besides, there is a grammer conflict with the ternary operator "cond ?
one : two".  That could be solved by using something else instead of the
colon.

Anyway, I think the label should be close to the WHILE.

I have been using the ".something" notation in other places:

        FUNC.abstract RetType funcy(ArgType arg)
        FUNC.default RetType funcy(ArgType arg)

I'm not sure if, for consistency, the same syntax should be used for the
loop label, or we should intentionally do it differently, so that it's
clear a different mechanism is being used.  Let's look at a few
examples.

Using a slash:

         WHILE/loop  asdfsdf == asdf.asdf.asdf()
           FOR i IN myList
             IF bad(i)
               BREAK/loop
             }
             IF last(i)
               CONTINUE/loop
             }
             merge(i)
           }
         }
         IF loop.breakUsed
           foundBad()
         ELSE
           writeResult()
         }

Using a dot:

         WHILE.loop  asdfsdf == asdf.asdf.asdf()
           FOR i IN myList
             IF bad(i)
               BREAK.loop
             }
             IF last(i)
               CONTINUE.loop
             }
             merge(i)
           }
         }
         IF loop.breakUsed
           foundBad()
         ELSE
           writeResult()
         }

I tend to prefer WHILE/loop.

--
ARTHUR: Charge!
   [They all charge with swords drawn towards the RABBIT.  A tremendous twenty
   second fight with Peckinpahish shots and borrowing heavily also on the
   Kung Fu and karate-type films ensues, in which some four KNIGHTS are
   comprehensively killed.]
ARTHUR: Run away!  Run away!
                 "Monty Python and the Holy Grail" PYTHON (MONTY) PICTURES LTD

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